This hadeeth comes under the following chapter: PRAYER DURING THE NIGHT AND THE NUMBER OF THE RAK'AHS WHICH THE APOSTLE (SALLALLAAHU ALAYHI WA SALLAM) OBSERVED IN THE NIGHT AND OBSERVANCE OF ONE RAKIAH OF WITR
Abu Salama asked 'A'isha about the prayer of the Messenger of Allaah (sallAllaahu alayhi wa sallam) She said: He observed thirteen rak'ahs (in the night prayer). He observed eight rak'ahs and would then observe Witr and then observe two rak'ahs sitting, and when he wanted to bow he stood up and then bowed down, and then observed two rak'ahs in between the Adhan and lqama of the dawn prayer.